Dead Power Supply(XAD819AR) for Acer AL1706

[Aeridyne]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Little update, on one of the AL1706b monitors, this was one that would not turn on at all. Totally dead. None of the caps look bad on it. Tried plugging in different ccfl lamp to each of the 4 outputs, no change, still wouldn't power on. I think the issue with this one could be different from the others.

On one of the V173, the ones that I can usually get to display a 98 640x480 image if I connect it and then turn it off and back on again, I had one all disassembled and tried the same thing with the lamps, when I plugged the spare ccfl into socket 4 (labeled CN503), the bulbs came on as they always do for a half second, go off, but then they came back on again and stayed. This was connected to a Windows 7 system with 1024x768 resolution. So, I thought that I had finally figured out the issue at least with those, which I have six of. I took apart the actual panel to get at that bulb.... And there does not appear to be anything wrong with it? Both of the solder points are perfect still, no signs of burning or anything. At a loss as to how to fix these.

[Aeridyne]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

I see this thread is a bit old at this point but I must revive it and it seems the most fitting place on the net for the question...

I have two Acer AL1706b monitors and six Acer V173 monitors.

They pretty much all do the same thing, plug it in, power led will come on. If connected to computer, power led changes from orange to blue. If not connected, most of them show "no signal" clearly. They also will show logo clearly when first powered up. Some do not, but power led is same behavior on all. Most I can get to display computer briefly, then goes black again. If I plug into a 98 system at 640x480 resolution I can get some of them to display and stay on after turning it off and on again. None will display anything else for any length of time. Only exception being I replaced a few caps on one and it displayed an XP at 1024x768 but the image was wavy, like refresh was off. Then it wouldn't display at all again.

Only one of them appeared to have a bad capacitor. One one of them I replaced all of the large capacitors except the biggest one, and the tiny ones.

I removed every single capacitor from one of the boards and tested with a nice Matco meter that has a "Cap" function and they all got up to the correct value uf, so I assume that means they are all actually "good".

The issue is no matter how many caps I replace, like the original poster and it seems some others, the issue persists unchanged.

Being that some can actually display and turn on and look fine on the 98 system at low res, the backlights seem fine. I'm at a loss as to what to replace on these for full function? There are 3 similar ICs on each board, I can post numbers tomorrow.

Any ideas to get these going would be great. One guy did mention power ICs but was quite sparse on any relevant thoughts beyond that.

[budm]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

All I can tell you is that I use PANASONIC FM/FC/FR series for all my repair, the power supplies for the monitor and TV are not that tightly regulated.

[akatz]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Hi All,

I'm also working on an Al1706 monitor. My issue is that the monitor always turns on, but usually shows the warm-up screen with the Acer logo, and then the power led blinks off, back on, and then repeats this cycle over and over. However, sometimes the monitor turns on and works just fine, but usually not.

In any case, I need a bit of help finding the replacement caps. I am trying order everything from DigiKey for convenience.

All of the old capacitors are from the CapXon KF Series ()

I would like to replace three [470uF, 25V, 1200 mA ripple, .076 Ohm impedance] caps with http://www.digikey.com/scripts/DkSea...45202870054504

I would like to replace two [1000uF, 10V, 1040 mA ripple, .076 Ohm impedance] caps with http://www.digikey.com/scripts/DkSea...45202870054504

I would like to replace one [22uF, 50V, 150 mA ripple, 1.25 Ohm impedance] cap with http://www.digikey.com/scripts/DkSea...45202870054504

I am having a lot of trouble finding a replacement for the [470uF, 10V, 580 mA ripple, 0.250 Ohm impedance] cap on DigiKe because everything with a suitable ripple current has a listed impedance far below the old capacitor impedance (50% or so).

I think this is my main stumbling block. I do not want to choose a new capacitor with impedance so low that it creates circuit instability but I do not know how low I can go before that happens. Any and all help is greatly appreciated.

Also, I apologize for digging up a 2+ year old thread, but this seemed like the appropriate thread for this question.

[kak3ch]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Another Acer AL1916W with the same TDK XAD819R/EA02819X supply fixed by replacing all 11 caps.

Thanks for postings,
Kal

[perszebutol]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Hi


I was here about 2 years ago, i replaced the capacitors of my Hanns G HN 198 D monitor. This was the only place where I could find proper instructions to my problem. ( I had to replace all the capacitors, because the monitor couldnt even be turned on.) However I'm writing now because of other issues. It might not be the right place to ask, but unfotrunately I couldnt find any better topic, which deals with the replacement of CCFL to LED backlit. I can't do it without the shcematic of the TDK XAD819R/EA02819X supply. If anyone could share this with me, would be much appreciated.


Thanks, perszebutol

[budm]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Here are more pictures:
http://s807.photobucket.com/albums/y...Acer%20AL1706/

[jimbob111]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

got to searching and found this picture that answers my question.

https://www.badcaps.net/forum/showpo...83&postcount=4

great site

[jimbob111]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Hi All - I changed the caps on my XAD819AR a few months ago and got the monitor running. Unfortunately I used ratshat parts and the monitor went out last weekend (maybe just a coincidence but you never know). After reading this excellent thread I bought new caps from digi-key and just put them in. As I was inspecting my work I noticed that there was a resistor called out (R16) near the center of the board that was missing! It's close enough to the cap I replaced (C10) that it may have fallen off. Trouble is I have no idea if it was truly installed or intentionally missing (I see other NI parts on the board). Can someone either post a picture of the bottom of the board or look at one and tell me if R16 is there and what value it might be.

thanks in advance

jimb

[Marsupial]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

I find it quite amusing that they made all those revisions, and it was always the same problem to raise...

I changed a bulged cap on mine, which is a different version (non-TDK) but behaved the same way; result is a working monitor.

Well, I changed other caps while I had it open; same company, likely bulging waiting to happen. Funny how the replacement caps (same specs, down to the temperature rating) ended up being smaller than the faulty ones.

Wanted to say thanks to all who got involved in this thread, this site is a mine of valuable information!

[Marsupial]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Well, I mean it is not even remotely related. I guess they got away from the TDK boards and replaced it with one by another company.

[retiredcaps]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

That's weird, the power board on my AL1706 is different than both ones pictured in this thread.

Not really. Manufacturers can and have changed power boards, but kept the same model number. That is why we always insist on pictures of your board versus stock or reusing photos.

[Marsupial]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

That's weird, the power board on my AL1706 is different than both ones pictured in this thread. There's one bulging capacitor, sadly I don't have any replacement in stock.

Delays, delays. lol.

Thanks everyone who participated in this thread for all the references.

[Marsupial]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Well, apparently, pryint it open was the way. I ended up taking the cover out. Now the real troubleshooting can begin.

[Marsupial]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Sorry for reviving an old thread...

I have the same model, same problem.

AL1706 turns on, I actually see the logo and then the signal from the computer for a brief moment (maybe half a second) before the backlight turns off. I figure, all works but the backlight controller or power supply.

Before attempting any kind of recap job, I have a more problematic question. How do we open these monitors? I can't find out how to remove the cover. I removed the stand, the only screws I could find.
I've considered prying it out, but aside from marking the casing, I don't think I'll achieve anything worthy.

What's the trick?

[Skoffer]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

I've fixed about 15 of these Acer monitors. They are the easiest monitors that I have come across to fix.

But, I had a few of them that gave me some grief, and it turned out to be burnt out backlights. Keep that in mind. The backlights are relatively easy to replace in these panels, you just have to be sure not to jolt the actual LCD too hard and rip one of the ribbons from the panel logic board. <-speaking from experience. I currently have a 17 inch panel that no longer works because I ripped one of the ribbons. But I use the backlights from this panel for testing.

Another good thing about that specific Acer line is that all of the different sizes use nearly identical PSU boards. So, I have been able to swap the PSU from a 1706 or 1716 and put it into a 1916W and a 2016 for quick repairs. Easy easy easy boards to work with. These monitors have made me quite a bit of money.

[PlainBill]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Hey Bill , thanks for your answer.

So in your experience , a corrupt eeprom memory would prevent the unit from powering on?Think i remember having to repeteadly try to turn it on before use until it finally died.

Would you suggest a replace on those caps?

First of all, replace all bulging caps; better yet, replace ALL electrolytic caps on the power supply with the possible exception of the large 450 volt one.

The signal card can be thought of as a special purpose computer. Most graphics processors have only a small piece of bootstrap code which loads the actual firmware from a serial eeprom. User data (brightness, contrast, current status, etc) should be stored in a second serial eeprom. When the power supply starts the graphics processor retrieves it's programming from the program serial eeprom. It then loads the 'last known state' from the user eeprom. A power supply rail with excessive noise makes writing to and reading serial eeproms prone to error. If program storage is corrupted, the graphics processor is 'brain dead'. If user storage is corrupted, some processors flash the power led rapidly to indicate a problem.

PlainBill

[Aikiotto]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Hey Bill , thanks for your answer.

So in your experience , a corrupt eeprom memory would prevent the unit from powering on?Think i remember having to repeteadly try to turn it on before use until it finally died.

Would you suggest a replace on those caps?

[PlainBill]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Hello guys , grats on the great site!

Out of boredom I´ve opened an old AL1706 that wont turn on (just a quick flash on the led) the power board just the same that was posted on a pic on the previous page , a few caps do look bloated , measurements on the out pins 12+ :13.4v 5v+ :5.15 GND: -0.047.

Would bad caps cause this kind of erroneous outputs?!

Thanks in advance
Aiki

Those voltages aren't unreasonable. The 12 volt rail normally runs high when the inverter is off, and the 5 volt rail is normally 5.2, so it's right on.

However, the readings don't show how much noise is on the 5 volt rail, and if the caps are bad enough it will cause problems for the processor on the signal card. It isn't impossible that that has already happened. Sometimes if the problem persists long enough the eeprom on the signal board gets corrupted.

PlainBill

[Aikiotto]

Re: Dead Power Supply(XAD819AR) for Acer AL1706

Hello guys , grats on the great site!

Out of boredom I´ve opened an old AL1706 that wont turn on (just a quick flash on the led) the power board just the same that was posted on a pic on the previous page , a few caps do look bloated , measurements on the out pins 12+ :13.4v 5v+ :5.15 GND: -0.047.

Would bad caps cause this kind of erroneous outputs?!

Thanks in advance
Aiki